Alert archive / Oklahoma / Severe Thunderstorm Warnings in 2011

Severe Thunderstorm Warning 427, NWS Norman, OK

July 13, 2011Caddo County, Oklahoma

NWS Norman, OK issued this severe thunderstorm warning at Jul 13, 2011, 2:31 PM CDT for Caddo County, Oklahoma. It was in force for 44 min. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued: Jul 13, 2011, 2:31 PM CDT (19:31 UTC)
Expired: Jul 13, 2011, 3:15 PM CDT
In force: 44 min
Issued by: NWS Norman, OK
Area: Storm-based polygon

County Caddo County, OK

The radar

The Norman radar (KTLX), 101 km from the middle of the area, began a volume at 19:33 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

The nearest sounding before it

Norman, OK (KOUN), launched 12:00Z, 7.5 hours before the alert went out and 89 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.

Mixed-layer CAPE: 1440 J/kg
Mixed-layer CIN: -158 J/kg
Mixed-layer LCL: 1656 m above ground
0-6 km bulk shear: 13 kt
0-1 km storm-relative helicity: 82 m²/s²
0-3 km storm-relative helicity: 107 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this severe thunderstorm warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Norman, OK wrote its last area forecast discussion before this severe thunderstorm warning went out at Jul 13, 12:39 PM CDT, 1 hour 52 minutes earlier.

Area forecast discussion, Jul 13, 12:39 PM CDT, 1 hour 52 minutes before

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Hazardous weather outlook, Jul 13, 11:55 AM CDT, 2 hours 36 minutes before

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE NORMAN OK
1155 AM CDT WED JUL 13 2011

OKZ004>048-050>052-TXZ083>090-141000-
HARPER-WOODS-ALFALFA-GRANT-KAY-ELLIS-WOODWARD-MAJOR-GARFIELD-NOBLE-
ROGER MILLS-DEWEY-CUSTER-BLAINE-KINGFISHER-LOGAN-PAYNE-BECKHAM-
WASHITA-CADDO-CANADIAN-OKLAHOMA-LINCOLN-GRADY-MCCLAIN-CLEVELAND-
POTTAWATOMIE-SEMINOLE-HUGHES-HARMON-GREER-KIOWA-JACKSON-TILLMAN-
COMANCHE-STEPHENS-GARVIN-MURRAY-PONTOTOC-COAL-COTTON-JEFFERSON-
CARTER-JOHNSTON-ATOKA-LOVE-MARSHALL-BRYAN-HARDEMAN-FOARD-WILBARGER-
WICHITA-KNOX-BAYLOR-ARCHER-CLAY-
1155 AM CDT WED JUL 13 2011

THIS HAZARDOUS WEATHER OUTLOOK COVERS NORTHERN...WESTERN...
CENTRAL...AND SOUTHERN OKLAHOMA...AND WESTERN NORTH TEXAS.

.DAY ONE...TODAY AND TONIGHT...

THUNDERSTORM OUTLOOK...
SCATTERED THUNDERSTORMS ARE EXPECTED INTO THE EVENING ACROSS
OKLAHOMA AND WESTERN NORTH TEXAS. A FEW MAY PRODUCE DAMAGING WIND
GUSTS.

DISCUSSION...
A MOIST AND UNCAPPED ATMOSPHERE OVER OKLAHOMA AND NORTH TEXAS WILL
PROVIDE AN ENVIRONMENT FAVORABLE FOR AT LEAST ISOLATED THUNDERSTORMS
THROUGH LATE EVENING. IN ADDITION...AN OUTFLOW BOUNDARY EXTENDING
FROM NORTHWEST TO SOUTH-CENTRAL OKLAHOMA WILL PROVIDE A FOCUS FOR
STORM DEVELOPMENT. SCATTERED STORMS ARE EXPECTED TO FORM...AND
GRADUALLY INCREASE IN COVERAGE...THIS AFTERNOON. COVERAGE AND
INTENSITY OF STORMS SHOULD BEGIN TO DECREASE BY SUNSET...BUT A FEW
STORMS MAY PERSIST WELL INTO THE NIGHT. MODERATE INSTABILITY AND
VERY WEAK VERTICAL WIND SHEAR SUGGEST THAT THE PRIMARY RISKS WITH
STORMS WILL BE HEAVY RAIN AND STRONG WIND GUSTS.

PROBABILITY TABLE...
VALID THROUGH 700 AM CDT THURSDAY JUL 14.
PROBABILITY OF THUNDERSTORMS OCCURRING IN THE
                  NWS NORMAN COUNTY WARNING AREA...100 PERCENT.
PROBABILITY A PARTICULAR STORM WILL BECOME SEVERE...40 PERCENT.

OTHER HAZARDOUS WEATHER...
EXCESSIVE HEAT IS EXPECTED THIS AFTERNOON...ESPECIALLY OVER SOUTHERN
OKLAHOMA AND ADJACENT PARTS OF NORTH TEXAS. A HEAT ADVISORY
CONTINUES.

.DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY...

THUNDERSTORM OUTLOOK...
SCATTERED AFTERNOON AND EVENING THUNDERSTORMS WILL BE POSSIBLE INTO
THE WEEKEND...BUT ANY RELIEF FROM THE HEAT WILL BE VERY BRIEF.

OTHER HAZARDOUS WEATHER...
EXCESSIVE HEAT IS EXPECTED TO PERSIST AND THE HEAT ADVISORY IS
EFFECTIVE UNTIL SATURDAY. FIRE DANGER WILL BE VERY HIGH ON FRIDAY.

THE NEXT SCHEDULED HAZARDOUS WEATHER OUTLOOK WILL BE ISSUED AT 5 AM
THURSDAY.

CMS

In the hours before

Special weather statement, Jul 13, 1:41 PM CDT, 50 minutes before

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Special weather statement, Jul 13, 2:27 PM CDT, 4 minutes before

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE NORMAN OK
227 PM CDT WED JUL 13 2011

OKZ023-132000-
CADDO OK-
227 PM CDT WED JUL 13 2011

...SIGNIFICANT WEATHER ADVISORY...

THIS SIGNIFICANT WEATHER ADVISORY IS FOR CADDO COUNTY.

AT 226 PM CDT...A STRONG THUNDERSTORM WAS LOCATED 5 MILES NORTHWEST
OF ANADARKO...MOVING EAST AT 15 MPH. THIS STORM WILL AFFECT HIGHWAY
281 FROM ANADARKO TO GRACEMONT.

HAZARDS INCLUDE...
HAIL UP TO ONE-HALF INCH...
WIND GUSTS TO 50 MPH...
CLOUD TO GROUND LIGHTNING...

LAT...LON 3533 9823 3525 9809 3503 9809 3494 9836
      3517 9844

BURKE

The office that day

Everything else NWS Norman, OK issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jul 12, 7:05 PM CDT	Special Weather Statement	OUN	Cleveland, McClain	25 min
Jul 12, 7:23 PM CDT	Special Weather Statement	OUN	Hughes	22 min
Jul 12, 7:27 PM CDT	Special Weather Statement	OUN	Cleveland	33 min
Jul 12, 7:30 PM CDT	Special Weather Statement	OUN	Pottawatomie	30 min
Jul 12, 7:40 PM CDT	Special Weather Statement	OUN	Blaine	35 min
Jul 13, 3:20 AM CDT	Special Weather Statement	OUN	Kay	55 min
Jul 13, 4:17 AM CDT	Areal Flood Advisory	OUN	Kay	3 hr
Jul 13, 1:41 PM CDT	Special Weather Statement	OUN	Beckham	34 min
Jul 13, 2:27 PM CDT	Special Weather Statement	OUN	Caddo	33 min
Jul 13, 2:59 PM CDT	Special Weather Statement	OUN	Cotton, Jefferson, Tillman	61 min
Jul 13, 3:05 PM CDT	Special Weather Statement	OUN	Grady	25 min
Jul 13, 3:26 PM CDT	Special Weather Statement	OUN	Roger Mills	34 min
Jul 13, 3:33 PM CDT	Special Weather Statement	OUN	Blaine	42 min
Jul 13, 3:47 PM CDT	Special Weather Statement	OUN	Canadian	43 min
Jul 13, 3:53 PM CDT	Severe Thunderstorm Warning	OUN	Blaine, Caddo, Canadian, Kingfisher	67 min
Jul 13, 4:24 PM CDT	Severe Thunderstorm Warning	OUN	Blaine, Kingfisher, Major	51 min
Jul 13, 4:44 PM CDT	Severe Thunderstorm Warning	OUN	Kingfisher	31 min
Jul 13, 5:02 PM CDT	Special Weather Statement	OUN	Major	43 min
Jul 13, 5:09 PM CDT	Severe Thunderstorm Warning	OUN	Alfalfa, Garfield, Major, Woods	51 min
Jul 13, 5:20 PM CDT	Severe Thunderstorm Warning	OUN	Kingfisher	40 min
Jul 13, 5:24 PM CDT	Special Weather Statement	OUN	Grady	51 min
Jul 13, 5:37 PM CDT	Special Weather Statement	OUN	Murray	38 min
Jul 13, 5:41 PM CDT	Severe Thunderstorm Warning	OUN	Alfalfa, Garfield, Major, Woods	49 min
Jul 13, 6:02 PM CDT	Severe Thunderstorm Warning	OUN	Cleveland, McClain	43 min
Jul 13, 6:10 PM CDT	Special Weather Statement	OUN	Woods	35 min
Jul 13, 6:14 PM CDT	Special Weather Statement	OUN	Pottawatomie	46 min
Jul 13, 6:22 PM CDT	Severe Thunderstorm Warning	OUN	Pottawatomie	53 min
Jul 13, 6:26 PM CDT	Special Weather Statement	OUN	Caddo	34 min
Jul 13, 6:57 PM CDT	Special Weather Statement	OUN	Caddo, Kiowa	33 min
Jul 13, 5:35 PM CDT	Special Weather Statement	OUN	Clay	25 min

Nearby

Severe Thunderstorm Warnings in Oklahoma, 2011 Every severe thunderstorm warning in 2011

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.